Identifying Male & Female Monarch Butterflies

We had our first Monarch visitor to the Waystation today! While he didn't stick around long enough for me to snap a picture, I was able to determine that he was definitely a male. How do we distinguish our lovely ladies from our handsome gentlemen? It can be difficult to tell while in flight, so we have to wait for them to land for a closer look....

Hmmm, a tough one. What about this one?

Also a tough one! Our first photo is a female Monarch; she has thicker black veins on her wings. The second is a male! He has thinner black veins and a spot on each back wing. Can you spot the spot? Here's a closer look:

From here on out, we will be on Butterfly Watch! I will update the blog when I see evidence of egg laying for any of the butterflies or moths that visit the Waystation.